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Vitorsworkshop

1.
Multi Satellite Reception
4 Antennas
– Perfectly
Hidden
130 TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 01-02/2014 — www.TELE-audiovision.com
• permanent installation required
no
•
not visible from the street since the system is lower
than a balcony wall
•
better reception than with a single multi-feed
antenna
•
easy set-up since only one antenna needs to be
aligned
•
low-cost thanks to standard components
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131

2.
Multi Satellite Reception
Antenna array on the balcony
– without your neighbour or
landlord having a clue
Vitor Martins Augusto
If you live in a rented apartment
or in a condo the following might
ring bell: You prefer the endless
possibilities of satellite reception
over cable or terrestrial channels,
but you’re not allowed to install a
satellite antenna on your balcony,
let alone on the building’s facade.
If you believe you’ll be stuck with
that situation forever, we have
news for you. We’ve come up with
a real treat that should even impress the odd satellite DXer. But
let’s not get over-excited and
rather start right from the beginning.
When I strolled through my local DIY
centre recently I also walked through
the satellite section, as I always do,
only to find out that stand-alone antenna poles are way too expensive. 49
euros for a small piece of galvanized
steel? Come on!
Actually, I have one of those at
home already, and it does a brilliant
job for use on a balcony without having to drill a whole into the existing
1
building structure. But let’s be honest,
multi-feed reception with a 60cm offset antenna is not exactly the perfect
solution and – come to think of it – I
originally wanted to receive a total of
four positions anyway: 28.2E, 19.2E,
13.0E and 30.0W. This requires at least
two antennas, and this was also why I
was on the lookout for a second pole
in the first place. One that I could use
without permanent installation. Because my landlord would never allow
that. Period.
Disappointedly, I trotted away, passing a display of workbenches along
my way when all of a sudden my eyes
wandered towards this foldable base
which was meant to support a heightadjustable table. This would do nicely
for hanging wallpaper, but in actual
fact my thoughts had long gone from
home improvement to something entirely different: What if I turned that
foldable base by 90 degrees and used
it as perfectly suitable antenna poles
for four individual antennas? A quick
look at the attached price tag meant
that it could be mine for 23 euros, and
so a decision was taken on the spot.
Minutes later, I carried home an inconspicuous foldable base that would be
turned into excellent stand-alone antenna poles. The base looked a bit low,
though, and frankly I had some doubts
as to whether 60cm antennas could be
mounted on them at all. And whether
those antennas would actually allow
decent reception in the end.
As it turned out, it was a very tight
job with only a couple of centimetres
clearance between antenna and balcony floor. Nonetheless, I had a signal
coming in, which proved that recep-
4
1. Existing stand-alone antenna
pole. Cost: around 40 to 50 euros.
2. Foldable base for DIY table. Cost
in the DIY centre: around 25 euros.
3. Create an improvised antenna
pole by turning the foldable base by
90 degrees.
4. Comparison of height and space
requirements of both solutions.
5. 60cm offset antenna: Barely fits
into available space.
2
3
132 TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 01-02/2014 — www.TELE-audiovision.com
5
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133

3.
6
6. Inside the flat antenna: It’s more like a
prime focus antenna with reflector. The
LNB is mounted behind.
7. Size comparison between a 60cm offset
antenna and a 60cm prime focus flat
antenna.
7
tion was possible. On the down side, I
found that a maximum of three offset
antennas could be mounted, since the
space required by the feed arms and
the LNBs did not allow for a fourth antenna. Still, at this point I simply refused to give up and thought long and
hard about how I could accomplish a
small and – almost – invisible antenna
farm on my balcony after all.
I decided to get four flat antennas.
The models I chose were not flat antennas in the true sense of the word,
but rather prime focus antennas that
feature a metal dish behind the plastic covering on the front, which means
that the LNB is actually positioned behind the antenna. This a very smart
design that allows for virtually flat antennas which still achieve a good signal
gain that is in line with most conventional 60cm antennas.
Genuine flat antennas, on the other
hand, use a multitude of small patches that are connected to each other.
Signal gain with such a construction
can only grow logarithmically with regard to the number of patches that are
used, which means that those antennas are usually only available in small
sizes (comparable to 60cm antennas)
and are more expensive – one of the
reasons why I did not opt for genuine
flat antennas.
When I tested only one antenna for
the first time the results I obtained
were truly promising. I was able to receive a perfect signal right on my balcony, behind the balcony wall.
Next, I had to mount the remaining
134 TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 01-02/2014 — www.TELE-audiovision.com

4.
three antennas. Taking into account
the extremely low clearance between
the individual antennas I had to figure
out the best possible arrangement.
For position 1 I chose ASTRA2 (28.2E),
followed by ASTRA1 (19.2E) for position 2, HOTBIRD (13.0E) for position 3
and finally HISPASAT (30.0W) for position 4. This way no single antenna was
blocked by another one and – equally
important – antennas in the front were
not in the way of the two antennas behind. What’s more, this set-up seemed
to be a logical choice to begin with.
With the help of professional signal
meter SPAUN SPAROS 609 precise
alignment turned out to be child’s play
and did not take more than 15 minutes
for all four satellites. Once I had completed that job I went about laying out
and tailoring the required coax cables.
The four cables from the antennas
8
9
were first fed to a 4/1 DiSEqC switch
and from there to our AZBox ME test
receiver (see test report in TELE-satellite 02+03/2012). The moment of truth
came when I initiated a channel search
on all four positions, which yielded a
total of 2230 TV channels and 442 radio stations. Unfortunately, the BBC
transponder on ASTRA2 did not come
in strong enough due to the small size
of the prime focus flat antenna. While
this did not come as a real surprise I
should mention at this point that the
position is very worthwhile nonetheless, with channels such as Channel4
HD, among others.
The entire set-up is lower than my
balcony wall and the adjusted 4-pole
base is extremely robust. When a major thunderstorm moved through the
area the antennas did not even move a
single millimetre.
12
12. The SPAUN SPAROS 609 signal meter was
used to individually align each antenna. This
job did not take longer than 15 minutes, since
the first aligned antenna can be used as a
point of reference for the additional antennas.
10
11
8. Antenna pole base
with a single prime
focus flat antenna:
Due to uneven weight
distribution the
set-up is still slightly
shaky.
9. Adding the second
antenna: To make
sure the pole base
does not tip over
I continued with
position 3 rather than
position 2.
10. Once the second
antenna was installed
the base has become
sure-footed and
could not fall over
any longer. At this
stage it did not make
much of a difference
whether antenna 2 or
4 would be next.
11. Finished. With
each of the four
antennas taking its
space the overall
situation is quite
tight, but each
antenna has an
unobstructed line of
sight.
136 TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 01-02/2014 — www.TELE-audiovision.com
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5.
13
One of the huge benefits of the construction is that the antenna array is
freely positioned on the floor without any screws or additional fixtures.
A surface area of approximately 1.4
by 1.4 meters is occupied and total
height does not exceed 80 centimetres. With a distance of 1.2 meters
14
from the balcony wall I was able to
achieve perfect reception quality,
provided the view towards south is
unobstructed – but this is a general
rule for all antenna installations in the
northern hemisphere.
In order to fully check out the entire antenna array I also moved it to a
13. Fully cabled set-up: Doesn’t take up much
space and is lower than the balcony wall.
14. Shown for comparison: An offset
antenna requires an extra 50 centimetres
for its feed arm.
15. Antenna array on a small balcony:
Even with restricted space available it was
possible to receive signals from all four
positions.
15
138 TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 01-02/2014 — www.TELE-audiovision.com

6.
16
17
much smaller second balcony. Thanks
to its southern exposure, it was once
again possible to catch signals with
all four antennas. And what’s more,
since the height of the balcony wall
is 30 centimetres higher than that of
the antenna construction, the array is
completely hidden from outside view.
There are other advantages as well:
Two persons can easily carry the
completed structure and if you turn
it by 90 degrees it even fits through
a standard balcony door. This means
the antenna array can be stored away
when not in use to free up balcony
space.
Thanks to all four antennas being tightly attached to the base you
can also just move the whole thing in
any direction without having to worry
that the four antennas might need realignment afterwards.
In actual fact, not even a signal meter will be required: Simply move the
array until you have reception with one
antenna. The remaining three antennas will then automatically be aligned
as well, since their positions towards
each other have not changed. I don’t
know about you, but to me that’s really clever…
As you can gather, I am totally over
the moon with this set-up. Obviously,
you could also go for two 60cm multi-feed offset antennas (antenna 1:
28.2E, 19.2E and 13.0E; antenna 2:
30.0W), but due to the ‘cross-eyed’
LNBs which would have to be used the
actual signal gain would be inferior to
this array.
16. A bird’s eye view reveals just how little
space is required for the antenna array.
17. A total of five antennas are positioned on
the small balcony – completely hidden behind
the balcony wall, yet perfectly suited for
state-of-the-art satellite reception and without
causing hassles with neighbours or landlords.
140 TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 01-02/2014 — www.TELE-audiovision.com